As an optical disk memory to which rewriting is capable, a magneto-optical disk memory is put to practical use, but a conventional magneto-optical disk memory has a disadvantage that when a diameter and an interval of a recording bit becomes smaller than a diameter of a converged semiconductor laser beam, a reproducing characteristic is deteriorated. This is because since an adjoining recording bit enters the converged laser beam, recording bits cannot be separately reproduced. In order to solve such a problem, Japanese Unexamined Patent Publication 5-81717/1993 (Tokukaihei 5-81717) discloses a method of separately reproducing recording bits by using a magneto-optical recording medium with a two-layer construction having (1) a reading-out layer, which is an in-plane magnetization film at a room temperature and becomes a vertical magnetization film as temperature rises, and (2) a recording layer which is a vertical magnetization film even if the recording bits are smaller than a diameter of a laser beam.
In Japanese Unexamined Patent Publication 5-81717/1993 (Tokukaihei 5-81717), even if a recording bit is smaller than a diameter of a laser beam, the recording bits can be separately reproduced, but as a recording medium, it is desired that density is further heightened and a recording characteristic is improved.